Basis of Presentation and Summary of Significant Accounting Policies - Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Sep. 30, 2023
Disaggregation of Revenue [Line Items]
Total revenue	$ 595,682	$ 572,544	$ 1,524,040	$ 1,561,380
Customer deposits	26,646		26,646		$ 27,577
Contract with customer, liability, revenue recognized	3,500		25,400
Homebuilding revenue
Disaggregation of Revenue [Line Items]
Total revenue	589,643	570,535	1,509,198	1,556,626
Land sales and other revenue
Disaggregation of Revenue [Line Items]
Total revenue	$ 6,039	$ 2,009	$ 14,842	$ 4,754